Rust on Cleveland pear
I planted a Cleveland pear last year. It looked good in the spring but later started to develop some spots on some of the leaves. Now the spots are on all of the leaves and the leaves are falling off prematurely. I put down 4 fertilizer spikes in the spring, also I have solid clay soil so I tried to plant the tree high
Wayne County Michigan
Originally the ornamental pears were considered very disease resistant but now their diseases are showing up. Our wet spring set the stage for European pear rust and it is very common in Eastern Michigan this year. Fungicides are used to protect the leaves in the spring. It is too late to do anything this year.
Here is a link to information about the disease.
European pear rust is related to Cedar apple rust and several other rust disease where cedar or juniper is one host and and a member of the apple genus (Malus) such as apple, pear, quince or hawthrone is the other. Here is a link to Cedar apple rust.
It has good pictures of what the disease looks like on juniper in the spring when it infects pear. If you have any juniper close by you can look in the winter for the galls. I attach a picture of a gall (teliohorn) I took in April before they really started to grow.